AirPlay is an Apple feature that many iOS users don’t know a lot about. For starters, it requires an Apple TV set-top-box, a gadget that isn’t nearly as popular as other Apple products. Additionally, the best parts of AirPlay only showed up late last year with the release of iOS 5. It’s relatively new territory, and thus often confuses people. The good news is that it’s not difficult to use and it’s an excellent way to get more out of your iDevices.

AirPlay has its origins in an old Apple feature called AirTunes. In the days of AirTunes (2004-2010), the only thing that you could stream was music from a computer running iTunes. That changed at the Fall iPod event in 2010 (which could very well end up being the last iPod event), when Steve Jobs rebranded the feature as AirPlay. With the name change came new functionality, including the ability to stream photos and videos from iOS devices.

So what’s this AirPlay thing all about? More importantly, how do you set it up?

How to use AirPlay

For basic AirPlay media streaming, things couldn’t be easier. You need to have an iOS device (like an iPad), an Apple TV set-top-box, and a WiFi connection. When all of that is setup, an AirPlay icon will show up in any of the following apps: Videos, Music (called iPod on pre-iOS 5 iPhones), Photos, or YouTube.

Once you select that icon, you’ll see a menu that lets you select your recipient device. If you have an Airport Express device, you can stream audio to it, otherwise select your Apple TV. After selecting, anything you play will be streamed to your TV.

How to use AirPlay Mirroring

Streaming some Ray Charles or a YouTube cat video is fine, but the real fun starts when you introduce AirPlay mirroring. It lets you mirror, in real-time, your iOS device’s display onto your TV’s display.

The big caveat here is that you will need one of Apple’s newest iOS devices (like the iPhone 4S or iPad 2) and the latest (2nd generation) Apple TV. If you have all of that, simply activate AirPlay mirroring by double-tapping your iOS device’s home button, and swiping the multitasking switcher over to the right (where the music controls are). There you’ll find the AirPlay icon — just tap it and select your Apple TV. At that point, anything that you do on your iPad will be displayed right on your TV.

It’s an exciting, but limited technology today. Expect to see more from it, and similar streaming technologies, in the future!